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Full-Text Articles in The Sun and the Solar System

Uncertainty In Solar Wind Propagation: An Analysis Of L1 To Earth Variability And The Implications For Geospace Modeling In Space Weather Operations, Espen T. Fredrick Jan 2025

Uncertainty In Solar Wind Propagation: An Analysis Of L1 To Earth Variability And The Implications For Geospace Modeling In Space Weather Operations, Espen T. Fredrick

Physics Dissertations - Archive

As humanity's technological dependence grows, so does its vulnerability to space weather. Space weather describes solar-driven phenomena in the near-Earth space environment and their terrestrial effects. Many of these effects occur due to the interaction of the solar wind and Earth's magnetosphere. The solar wind originates at the solar corona and carries solar plasma and magnetic field outward through the solar system. This magnetic field, known as the interplanetary magnetic field (IMF) during transit, can undergo magnetic reconnection with Earth's geomagnetic field when oppositely aligned field lines converge. This process transfers energy into Earth's magnetosphere, driving space weather phenomena.

Space …


The Earth's Magnetosphere, Soren Ormseth Jan 2018

The Earth's Magnetosphere, Soren Ormseth

Undergraduate Theses, Professional Papers, and Capstone Artifacts

The Interstellar Boundary Explorer (IBEX) is an Earth orbiting satellite launched in 2008; designed to map the boundary of our Solar System. In this presentation, we focus on how data collected by the IBEX-Hi sensor can be used to map the distribution of hot ions within the Earth's magnetosphere. As opposed to other satellites, IBEX images the magnetosphere from afar rather than by going through it. An improvement on the previous imaging techniques was developed, and we compare the new results to the old.


On The Dawn-Dusk Asymmetry Of The Kelvin-Helmholtz Instability Between 2007 And 2013, Z. W. Henry, K. Nykyri, T. W. Moore, A. P. Dimmock, X. Ma Oct 2017

On The Dawn-Dusk Asymmetry Of The Kelvin-Helmholtz Instability Between 2007 And 2013, Z. W. Henry, K. Nykyri, T. W. Moore, A. P. Dimmock, X. Ma

Publications

Using data from Time History of Events and Macroscale Interactions during Substorms (THEMIS), a statistical study was performed to determine whether a dawn-dusk asymmetry exists in the occurrence rates of the Kelvin-Helmholtz (KH) instability during Parker-Spiral (PS) and Ortho-Parker-Spiral (OPS) orientations of the interplanetary magnetic field (IMF). It is determined from the data that there is a strong preference toward the dawn side during PS orientation, and although a preference to the dusk side during OPS is suggested, this requires further study for an unambiguous confirmation. The uncertainty in the OPS result is due to a low number of events …


Influence Of Velocity Fluctuations On The Kelvin-Helmholtz Instability And Its Associated Mass Transport, Katariina Nykyri, Xuanye Ma, Andrew Dimmock, Claire Foullon, Antonius Otto, Adnane Osmane Sep 2017

Influence Of Velocity Fluctuations On The Kelvin-Helmholtz Instability And Its Associated Mass Transport, Katariina Nykyri, Xuanye Ma, Andrew Dimmock, Claire Foullon, Antonius Otto, Adnane Osmane

Publications

Kelvin-Helmholtz instability (KHI) and associated magnetic reconnection and diffusion processes provide plasma transport from solar wind into the magnetosphere. The efficiency of this transport depends on the magnetosheath and magnetospheric plasma and field properties at the vicinity of the magnetopause. Our recent statistical study using data from the Time History of Events and Macroscale Interactions during Substorms spacecraft indicates that the amplitude of the magnetosheath velocity fluctuations perpendicular to the magnetopause can be substantial. We have performed a series of local macroscale 2.5-dimensional magnetohydrodynamic simulations of the KHI during strongly northward interplanetary magnetic field and with the initial plasma parameters …


Determination Of Average Loss Lifetimes For Near‐Earth Electrons In Solar Storms, John Blears Mar 2013

Determination Of Average Loss Lifetimes For Near‐Earth Electrons In Solar Storms, John Blears

Undergraduate Theses—Unrestricted

The rate of electron wave‐particle scattering in the near‐Earth magnetosphere is investigated using multiple simulations of solar storms from solar cycle 23 (1996‐2005). Simulations are created using the Hot Electron and Ion Drift Integrator (HEIDI) model, which analyzes the drifts of keV‐energy electrons through the inner magnetosphere and identifies the precipitation of these particles into the upper atmosphere. The loss lifetime formulation used by HEIDI, which represents the rate at which the keV‐energy of the electrons is extinguished, predicts unreasonably large loss lifetimes deep in the inner magnetosphere. This discrepancy between the values used by the HEIDI model and those …